If you are only trying to avoid the dark damage, keep in mind how the dark damage mechanic works.
It only gives damage below light level 5 and only after a few time after you have been in the dark. The amount of time depends on how much time you spent in the light.
Taking this in account, unless its in my base, I have my light sources far away from each other so I would end up with 3 blocks with light level below 5. Since I will be moving, I will only be there for less then a second.
That allows me to have my light sources 16 blocks away from each other, if I recall correctly. Doing this, you save a lot in light sources!